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Semiconductor-based photocatalysts have become increasingly used in the removal of pollutants from wastewater, especially antibiotics. A series of composite-based cuprous oxide and bismuth vanadate (Cu2O/BiVO4) composite-based photocatalysts were synthesized by using the chemical method. The structure of the Cu2O/BiVO4 composite was verified by using x-ray diffraction, scanning electron microscopy, photoluminescence, Fourier transform infrared spectroscopy, and UV–visible spectra. The degradation of methylene blue (MB) and tetracycline (TC) was investigated to check the photocatalytic activity of the Cu2O/BiVO4 composite series. The quantity of Cu2O was varied from 1% to 7% by weight to prepare the series of Cu2O/BiVO4 composites. The analysis of results verified that 5% Cu2O/BiVO4 exhibits an outstanding photocatalytic activity as compared to 1%, 3%, and 7% Cu2O/BiVO4, pure Cu2O, and pure BiVO4 under visible light irradiation. The optimum value of photocatalytic degradation achieved with 5% Cu2O/BiVO4 was 97% for MB dye and 95% for TC in 120 min, which is greater than the photocatalytic degradation of pure BiVO4 (MB 45% and TC 72%), pure Cu2O (MB 57% and TC 80%), 1% Cu2O/BiVO4 (MB 72% and TC 85%), 3% Cu2O/BiVO4 (MB 83% and TC 88%), and 7% Cu2O/BiVO4 (MB 87% and TC 91%). The stability and reusability of Cu2O/BiVO4 were also investigated. To check the major role of trapping in degradation, a trapping experiment was also performed by using three trapping agents: BQ, EDTA, and tBuOH. The results showed that Cu2O/BiVO4 exhibits an improved photocatalytic activity in the degradation of antibiotics in polluted water because the recombination rate of the electron–hole pair decreased and the surface area increased, which increased the active sites for redox reactions. Such a photocatalytic composite with high efficiency has various applications, such as energy production, environmental remediation, and water remediation. [ABSTRACT FROM AUTHOR]

It is urgent to remove various pollutants from the water environment. Therefore, an inorganic–organic hybrid polyoxometalate (POM) [PMoVI6MoV2VIV8O44{Co(2,2′‐bipy)2(H2O)}4]‐[PMoVI4MoV4VIV8O44{Co(2,2′‐bipy)2(H2O)}2]·4H2O (PMoVCo) was fully characterized by XRD, XPS, FTIR, SEM, BET and zeta potential techniques, and applied for the catalytic reduction of hazardous methylene blue (MB), methyl orange (MO), rhodamine B (RhB), Cr (VI) and 4‐nitrophenol (4‐NP) in aqueous media over NaBH4 under mild condition. The removal ratios were 99.6% (MB, 2.5 min), 97.0% (MO, 3.0 min), 92.5% (RhB, 2.0 min), 89.2% (Cr (VI), 2.0 min) and 89.6% (4‐NP, 2.5 min), respectively. The pseudo‐first‐order rate constants of the reactions were 1.992 min−1 (MB), 0.810 min−1 (MO), 1.768 min−1 (RhB), 1.186 min−1 (Cr (VI)) and 0.934 min−1 (4‐NP), respectively. Additionally, PMoVCo exhibited satisfactory catalytic activity for the photo‐Fenton‐like degradation of MB at neutral pH under visible light irradiation with a degradation rate up to 99.9% in 480 min. The results of the recycling experiment prove that PMoVCo has high catalytic reusability. Moreover, the possible mechanisms of the catalytic reduction and degradation processes were proposed. The catalytic activities of PMoVCo are better than other inorganic–organic hybrid POMs. All the results of this study indicate that PMoVCo has the potential to be a satisfactory catalyst for wastewater remediation via reduction or photocatalytic degradation. [ABSTRACT FROM AUTHOR]

A novel, rapid, and facile method for one-step sonoelectrochemical synthesis of zinc oxide nanoparticles (UEZ) was introduced in this study. The optimum operating parameters have been selected at a voltage of 7.5 V, KCl concentration of 0.5 M, and the reaction time of 60 min. The as-prepared UEZ were characterized by XRD, SEM, and HRTEM. It was found that the UEZ has a hexagonal wurtzite structure with high crystalline quality, good purity, a size range of 30–100 nm, and good photocatalytic degradation of methylene blue. This work provides a facile route for large-scale synthesizing ZnO nanoparticles via anodization. [ABSTRACT FROM AUTHOR]

Herein, a series of N-doped Ti3C2/porous g-C3N4 composites are ultrasonically prepared from N-doped Ti3C2 and porous g-C3N4 under N2 atmosphere. The structure, morphology, and optical characteristics of the as-prepared composites are characterized by X-ray diffraction, transmission electron microscopy, scanning electron microscopy, X-ray photoelectron spectroscopy, UV-vis diffuse reflectance spectroscopy, etc. Moreover, photocatalytic measurements show that N-doped Ti3C2 is an excellent modifier for porous g-C3N4 to heighten its photocatalytic activity. Only 44.1% of rhodamine B can be degraded by the photocatalysis of pristine porous g-C3N4, while the photocatalytic degradation ratio of rhodamine B can reach up to 97.5% for the optimal N-doped Ti3C2 loading composites under visible light for 15 min. Moreover, the photocatalytic tests of N2 fixation confirm that the optimal composites show the highest production yield of NH4+ (11.8 μmol gcat−1 h−1), which is 2.11-folds more than that of porous g-C3N4 (5.6 μmol gcat−1 h−1). The reinforced photocatalytic properties are revealed to profit from the more photogenerated electrons and holes' separation, higher ability for light response, and more abundant active sites. This work develops the route for boosting the photocatalytic properties of porous g-C3N4 with N-doped Ti3C2. [ABSTRACT FROM AUTHOR]

The construction of Z-scheme heterojunctions is still a challenge. Structure tailoring and energy band engineering of metal–organic frameworks (MOFs) permit the rational design and fabrication of Z-scheme MOF/graphene oxide (GO) heterojunctions to enhance photocatalytic performance. Herein, a novel Z-scheme Zn-MOF/GO heterojunction as an environmentally friendly, reusable, and highly efficient visible-light-induced photocatalyst for methylene blue (Mb) decoloration and/or Cr(VI) reduction was synthesized. The Zn-MOF/GO composite displayed much higher photodegradation performance than pure Zn-MOF. Besides, the photocatalytic performance of composites is related to the amounts of GO, and Zn-MOF/GO(15%) showed the best activity. Specifically, Zn-MOF/GO(15%) presented 92.6% Mb decoloration, 98.8% Cr(VI) reduction, and the simultaneous removal of Mb (87.9%) and Cr(VI) (99.8%) with good stability. The improved performance for Zn-MOF/GO(15%) can be due to the formation of the Z-scheme heterojunction and built-in electric field, which can not only promote the photogenerated electron–hole separation and transfer, but also broaden the spectrum of light absorption. Furthermore, the improved plausible photodegradation mechanism of Zn-MOF/GO(15%) was provided, and e−, h+ and ·OH were the primary reactive species during the photodegradation reactions. [ABSTRACT FROM AUTHOR]

In this work, a new d10-configuration based Cd(II) coordination polymer (CP) with the formula [Cd2(CH3COO)2(bimb)2]·2ClO4 (1) have been synthesized using 4,4′-bis(imidazolyl)biphenyl (bimb) ligand and characterized. Single-crystal X-ray analysis reveals that the CP forms a 2D layer connected to a 3D supramolecular framework with weak packing interactions between benzyl and imidazolyl rings. CP 1 has been used as a photoluminescent sensor and a photocatalyst for the photodegradation of antibiotics, in particular nitrofurantoin (NFT). Sensing experiments indicate that 1 can selectively detect nitrofurantoin with a limit of detection of 0.025 μM, whereas when employed as a photocatalyst, CP 1 can photodecompose NFT up to 91.83% in a time span of 20 min. The decline in the photoluminescence intensity of CP 1 in the presence of NFT and the photocatalytic mechanism are addressed using theoretical calculations. [ABSTRACT FROM AUTHOR]

Advanced oxidative process is an efficient method to photocatalytically degrade the effluent pollution by organic dyes with a suitable catalyst. Photocatalysts with a heterojunction not only improve the excitation efficiency of the catalyst in the presence of light by broadening the wavelength range of absorption but also reduce the rate of recombination. ZnO and TiO2 were successfully synthesized in this study via solution combustion synthesis. Wurtzite ZnO was grown along with anatase TiO2 to create a heterojunction of ZnO–TiO2, and Co loading was carried out to improve the rate of electron transfer between the heterojunction for enhanced photocatalytic activity. The photogenerated electrons are injected from the conduction band of ZnO to TiO2via Co to create ˙O2− and holes from TiO2 to form OH˙, which help to degrade alizarin S. The detailed photocatalytic experiment confirmed Co/ZnO–TiO2 as an extremely efficient catalyst, which shows the complete degradation of the dye alizarin S in just 40 minutes under UV light illumination. [ABSTRACT FROM AUTHOR]

In this work, green method to synthesize chromium-doped zinc oxide (ZnO) nanorods (NRs) using an aqueous flower extract from Rhododendron arboretum is explored. Herein, chromium-doped ZnO NRs were prepared with different amount of chromium doping, varied as 2–10%. The green synthesized products underwent substantial analysis through X-ray diffraction (XRD), spectroscopic such as ultraviolet spectroscopy(UV-Vis) and scanning electron microscopy (SEM) methods. All samples were found to have hexagonal wurtzite ZnO, with average particle sizes of 52.41, 56.6, 54.44, 53.05, and 56.99 nm, respectively, for 2, 4, 6, 8, and 10% chromium doping in ZnO NRs. The Cr-doped ZnO NRs exhibited remarkable photocatalytic degradation activity of cationic dyes under UV-light, i.e., Malachite Green and Fuchsin Basic with degradation of 99.604 and 99.881%, respectively in 90 min. The reusability tests for these green synthesized Cr-doped ZnO NRs have also been carried out, showed 9–11 cycles with 85% of degradation efficiency. In addition, the Cr-doped ZnO NRs exhibited high selectivity for cationic dyes when experiments against mixture of dyes were performed. Photodegradation kinetics followed the pseudo-first-order model. The flower-extract-stabilized chromium-doped ZnO NRs demonstrated high photocatalytic activity toward malachite green and fuchsin basic dyes, potential material for pollution remediation. Cr-doped ZnO NRs by green method using flower extract of Rhododendon arboretum were prepared for the first time under ambient reaction conditions. Effect of Dopant i.e. Cr on Photocatalytic activity have been exploited. Selective photocatalytic degradation of cationic dyes i.e. MG, and FB has been achieved in 60–90 minutes. Optimization of reaction condition and various parameters has also been carried out. Recyclability of Cr-doped ZnO NRs was also evaluated and were found to be reusable for 11 cycles for degradation. [ABSTRACT FROM AUTHOR]

The removal of organic effluents from polluted water is a significant concern. Photodegradation of organic effluents can be performed using different photocatalysts. For this purpose, herein nickel cobaltite (NC) was prepared via the auto moisturization route and nickel sulfide (NS) via a hydrothermal approach. rGO-based nanocomposite (NC/NS/rGO) was synthesized using an ultrasonication approach. The as-prepared nanocatalysts were employed for bromophenol blue and diclofenac degradation. The outcomes of colored (bromophenol blue) effluent degradation by NC, NS, NC/NS, and NC/NS/rGO was found to be 42.65 %, 33.92 %, 56.19 %, and 81.44 %, respectively. The % degradation of diclofenac by NC/NS and NC/NS/rGO was realized to be 44.05 % and 65.98 %, respectively. NC/NS/rGO showed greater catalytic activity than other fabricated nanocatalysts due to the combined effect of nickel cobaltite and nickel sulfide and the existence of rGO. The rGO layers exhibited immense and active sites for the degradation reaction. A radical trapping analysis was performed to investigate the participation of active species in the photocatalytic reaction. [ABSTRACT FROM AUTHOR]

Flame spray pyrolysis is a novel fast-process for producing functional metal oxides. However, these functional nanomaterials are challenged with poor recyclability in water treatment from pollutants such as dyes. Herein, Bi 2 O 3 nanoparticles were produced by flame spray pyrolysis and spun together with eco-friendly cellulose acetate polymer into nanofiber membrane via electrospinning technique. The results reveal that cellulose acetate (CA) has good interaction with the particles, leading to reduced band gap, retardation of fast recombination of carriers and good electron transportation on the surface of the nanofiber membrane. The Bi 2 O 3 /CA nanofiber membrane records similar photocatalytic performance to that of flame-made Bi 2 O 3 nanoparticles, that is about 95% dye degradation at 90 min, which was far better than CA and Bi 2 O 3 /polyacrylonitrile nanofiber membranes. The electron spin resonance test and free radical scavenger test reveal that abundant hydroxyl radicals serve as the most active species that enhance photocatalytic degradation of dye on Bi 2 O 3 /CA nanofiber membrane. The flexible Bi 2 O 3 /CA nanofiber membrane also demonstrates easy recyclability after several runs with no significant decline in performance. This study pins the effectiveness of using eco-friendly cellulose acetate in obtaining inorganic-organic composite to concurrently achieve good photocatalytic performance and recyclability. [Display omitted] [ABSTRACT FROM AUTHOR]

The side effects of antibiotics on humans and ambient environment have aroused huge attention from related researchers. In this article, the performances and mechanism of photodegradation of tetracycline (TC) were examined by employing semiconducting polymer microspheres obtained with an emulsion-solvent-evaporation approach. Under the excitation of visible-light, as-prepared semiconducting polymer microspheres show outstanding photocatalytic ability and excellent stability for TC-derived antibiotics. Compared with corresponding semiconducting polymer powders, the adsorption and photocatalytic rates of TC by polymer-based microspheres increased by 8.07 and 6.79 times, respectively. These performance improvements in photodegradation are mainly ascribed to the larger specific surface area and longer conjugation length of as-prepared spherical structure. Characterization of electron spin resonance demonstrates that the primary active species functioning for efficient photodegradations of TC are superoxide radical, hydrogen peroxide, and hole. These results indicated that semiconducting polymer microspheres can serve as efficient photocatalysts for removing destructive TC-derived antibiotics from wastewaters. [ABSTRACT FROM AUTHOR]

A series of biodegradable composites, including maleic acid-grafted recycled poly(lactic acid) (g-rPLA) and chemically modified lyocell (m-lyocell), were successfully synthesized. The rPLA was obtained from waste PLA-based single-use coffee cups. The storage modulus at −20°C of g-rPLA was increased from 1920 MPa for pure PLA to 3370 MPa for 5 wt% g-rPLA/m-lyocell composites, which is more than 75% enhancement. The number-average molecular weight after photodegradation for 60 days of g-rPLA and 5 wt% g-rPLA/m-lyocell composites was decreased by about 67.12% and 26.17% as compared to the samples before photodegradation, respectively. The results of photodegradations for composites indicate that the change of number-average molecular weight after photodegradation decreased by increasing the loading of m-lyocell. This result suggests that the existence of m-lyocell improved the UV protection ability of the g-rPLA. With the enhancement of mechanical properties and UV protection ability, this work provides an appropriate approach for the applications to reuse the waste PLA-based single-use coffee cups. [ABSTRACT FROM AUTHOR]

Water pollution caused by antibiotics is a growing problem and photodegradation by efficient catalysts is an environmentally friendly technology that can effectively degrade organic pollutants in water. Here, a novel method was innovatively used to synthesize niobium oxyfluoride (Nb3O7F) nanosheets decorated with Au nanoparticles, which is the first report for the composites of Au and Nb3O7F. We prepared the Nb3O7F nanosheets via hydrothermal synthesis followed by deposition of Au nanoparticles on their surface using HAuCl4. The prepared samples were characterized by XRD, HRTEM, XPS, and UV-Vis. The diameters of most Au NPs are ranging from 5 to 25 nm with an average size of about 16.9 nm, as well as the Nb3O7F nanosheets in size ranging from 200 nm to 700 nm. The chemical composition of the Au-Nb3O7F showed a Au/Nb atomic ratio of 1/10, as well as a Nb/O/F ratio of 3/7/1. UV-Vis spectrum reveals a largest absorption peak at 520 nm for the Au-Nb3O7F nanosheets. The prepared Au-Nb3O7F nanomaterials were applied to the visible-light photodegradation of tetracycline hydrochloride, with the photocatalytic degradation rate reached more than 50% under the optimal conditions within 1 h. Capture experiments indicated that h+ and «O2- are the main active substances involved during the course of the photodegradation. Furthermore, the proposed mechanism for the photodegradation of the novel Au-Nb3O7F nanosheets was given. [ABSTRACT FROM AUTHOR]

A series of lanthanum‐doped ZnCr‐layered double hydroxide (La/ZnCr‐LDH) photocatalysts were successfully synthesized by a facial hydrothermal method and their photocatalytic activity for degradation tetracycline hydrochloride (TCH) were evaluated under visible light irradiation. The structure and physicochemical properties of the as‐synthesized photocatalysts were well characterized by X‐ray diffraction (XRD), transmission electron microscopy (TEM), Brunauer‐Emmett‐Teller (BET), X‐ray photoelectron spectrometer (XPS), and UV‐vis absorption spectroscopy. The photocatalyst with La doping content of 10 % (molar ratio La3+/(La3++Cr3+), La/ZnCr‐LDH‐10) has optimal performance for TCH removal (87.2 %) among all synthesized photocatalysts. Radical trapping experiments and Valence Band‐XPS (VB‐XPS) were used to propose a possible photocatalytic degradation process for TCH by La/ZnCr‐LDH‐10 photocatalyst. This strategy can be used to modify other photocatalysts for efficient removal of organic pollution in the environment. [ABSTRACT FROM AUTHOR]

One of the important research components of photocatalytic research is the development of new photocatalysts, and recent studies have shown the rise of borate‐type photocatalysts. This paper focuses on the photoreduction of potassium dichromate and the photodegradation of rhodamine B by two borate composites under simulated sunlight. A coral‐like borate was obtained by sol‐gel preparation and then assembled by photodeposition with Pt nanoparticles dots or CuO particles to obtain the new composites with excellent performance. The kinetic constants of photocatalytic properties of 2 %Pt/Gd0.85Ce0.15B5O9 and 2.5 %CuO/Gd0.90Ce0.10B5O9 samples in the reduction and degradation reactions are 0.0050 min−1 and 0.0150 min−1, which are 25 and 4.2 times of the intrinsic GdB5O9 sample respectively. The results of the study indicate the research promise of developing new visible photocatalysts based on borates, especially for photocatalytic applications for pollutant removal. [ABSTRACT FROM AUTHOR]

We report a family of donor‐acceptor thermally activated delayed fluorescent (TADF) compounds based on derivatives of DMAC‐TRZ, that are strongly photoreducing. Both Eox and thus E*ox could be tuned via substitution of the DMAC donor with a Hammett series of p‐substituted phenyl moieties while Ered remained effectively constant. These compounds were assessed in the photoinduced dehalogenation of aryl halides, and analogues bearing electron withdrawing groups were found to produce the highest yields. Substrates of up to Ered=−2.72 V could be dehalogenated at low PC loading (1 mol %) and under air, conditions much milder than previously reported for this reaction. Spectroscopic and chemical studies demonstrate that all PCs, including literature reference PCs, photodegrade, and that it is these photodegradation products that are responsible for the reactivity. [ABSTRACT FROM AUTHOR]

We report a family of donor‐acceptor thermally activated delayed fluorescent (TADF) compounds based on derivatives of DMAC‐TRZ, that are strongly photoreducing. Both Eox and thus E*ox could be tuned via substitution of the DMAC donor with a Hammett series of p‐substituted phenyl moieties while Ered remained effectively constant. These compounds were assessed in the photoinduced dehalogenation of aryl halides, and analogues bearing electron withdrawing groups were found to produce the highest yields. Substrates of up to Ered=−2.72 V could be dehalogenated at low PC loading (1 mol %) and under air, conditions much milder than previously reported for this reaction. Spectroscopic and chemical studies demonstrate that all PCs, including literature reference PCs, photodegrade, and that it is these photodegradation products that are responsible for the reactivity. [ABSTRACT FROM AUTHOR]

A type II heterostructured BiVO4/MIL-88B(Fe) composite was successfully synthesised for the photocatalytic degradation of tetracycline hydrochloride (TC-HCl) by a simple hydrothermal method. Thin film materials avoid secondary pollution of powder materials. The samples were characterised by XRD, SEM, TEM, XPS, UV-Vis DRS, and PL. The samples were also characterised for their optoelectronic properties. 3-BV/MIL-88B(Fe) (3 mmol BiVO4) was the most effective catalyst for the degradation of TCHCl, achieving 92.1% removal at 75 min with a degradation rate constant of 22.79 x 10-3 min-1. Moreover, durability evaluation and TC-HCl degradation potential evaluation were also performed. We looked into how TC-HCl concentration, pH and ions affect the degradation results. In order to determine the active ingredients, experiments for trapping free radicals and EPR tests were performed. The results indicated that the main active species were h+ and OH. It is proposed that a reasonable type-II heterostructure can help to explain the photocatalytic mechanism. The current study creates a stable photocatalytic system by compositing electrocatalytic and photocatalytic materials to achieve efficient antibiotic degradation and provides a viable strategy for future applications. [ABSTRACT FROM AUTHOR]

Photocages, also known as photoactivated protective groups (PPGs), have been utilized to achieve controlled release of target molecules in a non-invasive and spatiotemporal manner. In the past decade, BODIPY fluorophores, a well-established class of fluorescent dyes, have emerged as a novel type of photoactivated protective group capable of efficiently releasing cargo species upon irradiation. This is due to their exceptional properties, including high molar absorption coefficients, resistance to photochemical and thermal degradation, multiple modification sites, favorable uncaging quantum yields, and highly adjustable spectral properties. Compared to traditional photocages that mainly absorb UV light, BODIPY-based photocages that absorb visible/near-infrared (Vis/NIR) light offer advantages such as deeper tissue penetration and reduced bio-autofluorescence, making them highly suitable for various biomedical applications. Consequently, different types of photoactivated protective groups based on the BODIPY skeleton have been established. This highlight provides a comprehensive overview of the strategies employed to construct BODIPY photocages by substituting leaving groups at different positions within the BODIPY fluorophore, including the meso-methyl position, boron position, 2,6-position, and 3,5-position. Furthermore, the application of these BODIPY photocages in biomedical fields, such as fluorescence imaging and controlled release of active species, is discussed. [ABSTRACT FROM AUTHOR]

It's a promising way to address the global freshwater crisis and energy shortage through solar‐driven devices with evaporate, degrade, and generate electricity at the same time. Low‐efficient light‐thermal conversions for multi‐usage limit application. This paper presents a low‐cost melamine foam/TiO2/carbon black/bismuth (MF/TiO2/CB/Bi) composite with excellent activity to simultaneously process photothermal water evaporation, pollutant degradation, and thermoelectric output, namely‚ shooting three birds with one stone. Under 1 sunlight light intensity, the water evaporation rate reach 4.235 kg m−2 h−1, and the maximum electric power output of a single module is 0.733 W m−2. Meanwhile, Rhodamine B (RhB) solution with 4.0 × 10−4 mol L−1 can be almost degraded within 60 min. Excellent performance benefits from the enhanced adsorption by chemicals, 3D structure for accepting more incident light, and hydrophilic group reducing evaporation enthalpy. Combined with the simulation and experiment, the relationship between heat distribution and thicknesses is studied. When less than 1.98 cm, the lateral temperature is higher than the ambient temperature, thus additional energy cannot be obtained. This work provides a facile and novel method for the construction of photothermal conversion materials with multi‐functional, as a new and useful attempt to solve the shortage of fresh water and electric energy, as well as environmental pollution. [ABSTRACT FROM AUTHOR]

The efficient photogenerated carriers separation is the key factor in enhancing the activity of photocatalysts to solve environmental pollution problems. The internal polarized electric fields in polar materials most likely provide a more direct and stronger driving force for photogenerated carriers separation. Here, we investigate polar ε -Cd(IO 3) 2 (CIO) with two different morphologies as an efficient photocatalyst for the photodegradation of antibiotics and dyes. According to the theoretical calculation of the ratios of m h */ m e * along three different crystal axis directions, the photogenerated carrier separation efficiency along the c -axis direction is the largest, which matches the direction of the polarized electric field in the crystal. The internal polarized electric field promotes the separation of photogenerated carriers, leading to a high transfer efficiency of the catalyst. Moreover, photodegradation experiments demonstrate that the photocatalytic activity of CIO-1 is approximately 3 times that of TiO 2 P25. This study provides some insights that might aid the development of polar photocatalysts with superior performance. • ε -Cd(IO 3) 2 exhibits a excellent activity to photodegrade both antibiotics and organic dyes. • Residual dipole moment in ε -Cd(IO 3) 2 promotes separation rate of photogenerated carriers. • The polarization electric field in ε -Cd(IO 3) 2 is parallel to the c -axis direction. • Small m e * value along the c direction results in a high carrier mobility. • Large m h */ m e * ratio along the c direction results in efficient carrier separation. [ABSTRACT FROM AUTHOR]

Reactive oxygen species (ROS) have become an effective tool for tumor treatment. The combination of photodynamic therapy (PDT) and chemodynamic therapy (CDT) takes advantage of various ROS and enhances therapeutic effects. However, the activation of CDT usually occurs before PDT, which hinders the sustained maintenance of hydroxyl radicals (⋅OH) and reduces the treatment efficiency. Herein, we present a light‐triggered nano‐system based on molecular aggregation regulation for converting cancer therapy from PDT/photothermal therapy (PTT) to a long‐lasting CDT. The ordered J‐aggregation enhances the photodynamic properties of the cyanine moiety while simultaneously suppressing the chemodynamic capabilities of the copper‐porphyrin moiety. Upon light irradiation, Cu‐PCy JNPs demonstrate strong photodynamic and photothermal effects. Meanwhile, light triggers a rapid degradation of the cyanine backbone, leading to the destruction of the J‐aggregation. As a result, a long‐lasting CDT is sequentially activated, and the sustained generation of ⋅OH is observed for up to 48 hours, causing potent cellular oxidative stress and apoptosis. Due to their excellent tumor accumulation, Cu‐PCy JNPs exhibit effective in vivo tumor ablation through the converting therapy. This work provides a new approach for effectively prolonging the chemodynamic activity in ROS‐based cancer therapy. [ABSTRACT FROM AUTHOR]

Reactive oxygen species (ROS) have become an effective tool for tumor treatment. The combination of photodynamic therapy (PDT) and chemodynamic therapy (CDT) takes advantage of various ROS and enhances therapeutic effects. However, the activation of CDT usually occurs before PDT, which hinders the sustained maintenance of hydroxyl radicals (⋅OH) and reduces the treatment efficiency. Herein, we present a light‐triggered nano‐system based on molecular aggregation regulation for converting cancer therapy from PDT/photothermal therapy (PTT) to a long‐lasting CDT. The ordered J‐aggregation enhances the photodynamic properties of the cyanine moiety while simultaneously suppressing the chemodynamic capabilities of the copper‐porphyrin moiety. Upon light irradiation, Cu‐PCy JNPs demonstrate strong photodynamic and photothermal effects. Meanwhile, light triggers a rapid degradation of the cyanine backbone, leading to the destruction of the J‐aggregation. As a result, a long‐lasting CDT is sequentially activated, and the sustained generation of ⋅OH is observed for up to 48 hours, causing potent cellular oxidative stress and apoptosis. Due to their excellent tumor accumulation, Cu‐PCy JNPs exhibit effective in vivo tumor ablation through the converting therapy. This work provides a new approach for effectively prolonging the chemodynamic activity in ROS‐based cancer therapy. [ABSTRACT FROM AUTHOR]

Graphene‐like materials were prepared by thermal copolymerization using melamine as a precursor, and chemical methods successfully synthesized Eu/g‐C3N4 composites containing different europium elements. Degradation rates of 64.3 %, 91.9 %, and 72.8 % were observed in the photocatalytic degradation of Pefloxacin, Enrofloxacin, and Ciprofloxacin under visible light (λ>550 nm). Determine the photocatalytic activity of the composite. When the doping amount was Eu/g‐C3N4‐2 with k=0.0135 min−1, four times greater than that of g‐C3N4, the best photocatalytic effect was obtained. Repeated studies revealed that the Eu/g‐C3N4 composite samples had good cycle stability, and a potential degradation process was postulated. [ABSTRACT FROM AUTHOR]

A wide variety of borate materials are emerging as photocatalysts. Usually, the borates possess a large bandgap which limits their absorption of visible light, and the strategy of preparing nanocomposites is an effective way to enhance the absorption of light. X‐ray powder diffraction, infrared spectroscopy, Raman spectroscopy, scanning electron microscopy, and transmission electron microscopy were used to show that a three‐component nanocomposites was successfully prepared. For the photo‐degraded reactions of rhodamine B(RhB) and doxycycline hydrochloride(DH), the optimum composition of the ternary composite is a molar ratio of Gd0.9Ce0.1B5O9(GCBO) and g‐C3N4(CN) of 7 : 93, besides the mass of Cu is 2 % of the sum of the above two masses, and the ternary composite is abbreviated as 2Cu/CN@GCBO‐7. The kinetic constant for the photodegradation of RhB of sample 2Cu/CN@GCBO‐7 is 0.0580 min−1, which is 3.6 and 3.8 times that of non‐composite CN and GCBO. The mechanism postulated by free radical quenching experiments suggests that the importance of the three radicals is hole >⋅OH>⋅O2− in the photodegradation reaction. In addition, the kinetic constant for the photodegradation of DH of sample 2Cu/CN@GCBO‐7 is 0.0018 min−1, and the sample 2Cu/CN@GCBO‐7 has a hydrogen evolution rate of 11.8 μmol/h/g. [ABSTRACT FROM AUTHOR]

Zinc-doped CuAl2O4 (Zn-CuAl2O4) nanofiber membranes with a high specific surface area, multi-pore structure, and a partial inverse spinel structure were successfully fabricated by controlling the electrospinning process and calcination atmospheres. The excessive doping of Zn2+ ions results in the formation of ZnAl2O4/CuAl2O4 fiber membrane, which has a poor UV-Vis absorption ability. The diameter of Zn-CuAl2O4 nanofibers is about 80 nm, and the specific surface area of the Zn-CuAl2O4 nanofiber membrane is 45.2 m2/g. XRD and XPS results indicate that Zn-CuAl2O4 nanofiber membranes contain spinel and inverse spinel phases. Compared with pure spinel CuAl2O4 nanofiber membranes, the UV-Vis absorption ability of the Zn-CuAl2O4 nanofiber membrane is enhanced, and transient photocurrent intensity was increased from 0.14 mA/cm2 to 0.16 mA/cm2. The free radical capture experiments and EPR spectra indicate that huge ·O2− are generated on the surface of the Zn-CuAl2O4 nanofiber membrane, and the photocatalytic degradation efficiency of MB is increased by 14%. The Zn-CuAl2O4 nanofiber membranes exhibit excellent cycling stability and have great potential for photocatalytic degradation of dye wastewater. [ABSTRACT FROM AUTHOR]

Constructing heterojunction photocatalysts are widely applied to boost the photocatalytic activity of materials. Here, a novel covalent organic framework (COF) material with heptazine units was developed and hybridized with TiO2 nano particles (NPs) to fabricate the Heptazine‐COF@TiO2 photocatalysts for acetaminophen (AAP) photodegradation. The successfully assembled heptazine unit endows the Heptazine‐COF with outstanding semiconductor property (optical bandgap is 2.53 eV). The synthesized Heptazine‐COF@TiO2 hybrids is proved to have the heterojunction structure with high visible light activity and fast charge‐carrier mobility, and exhibits better performance in photodegradation of AAP under visible light. The excellent photodegradation efficiency (rate constant: 0.758 min−1) and high reusability (rate constant: 0.452 min−1 in the 6th cycles) of the optimized sample outperform the traditional inorganic photocatalysts and other heterojunction photocatalysts. In addition, these photocatalysts present universal degradation activity for other dyes and antibiotics. [ABSTRACT FROM AUTHOR]

In this study, carbon-quantum-dot (CQD)-decorated TiO2 was prepared using an ultrasonic doping method and applied in the photocatalytic degradation of naphthalene under sunlight irradiation. The CQDs were synthesized from a typical macroalgae via diluted sulfuric acid pretreatment and hydrothermal synthesis using an optimal design, i.e., 3 wt% and 200 °C, respectively. The CQD/TiO2 composite remarkably enhanced the photocatalytic activity. The degradation of naphthalene under a visible light environment indicated that there is a synergistic mechanism between the CQDs and TiO2, in which the generation of reactive oxygen species is significantly triggered; in addition, the N that originated from the macroalgae accelerated the photocatalytic efficiency. Kinetic analysis showed that the photocatalytic behavior of the CQD/TiO2 composite followed a pseudo-first-order equation. Consequently, our combined experimental approach not only provides a facile pretreatment process for bio-CQDs synthesis, but also delivers a suitable TiO2 photocatalyst for the visible environment along with critical insights into the development of harmful macroalgae resources. [ABSTRACT FROM AUTHOR]

Evaporative water concentration takes place in arid or semi-arid environments when stationary water bodies, such as lakes or ponds, prevalently lose water by evaporation, which prevails over outflow or seepage into aquifers. Absence or near-absence of precipitation and elevated temperatures are important prerequisites for the process, which has the potential to deeply affect the photochemical attenuation of pollutants, including contaminants of emerging concern (CECs). Here we show that water evaporation would enhance the phototransformation of many CECs, especially those undergoing degradation mainly through direct photolysis and triplet-sensitized reactions. In contrast, processes induced by hydroxyl and carbonate radicals would be inhibited. Our model results suggest that the photochemical impact of water evaporation might increase in the future in several regions of the world, with no continent likely being unaffected, due to the effects of local precipitation decrease combined with an increase in temperature that facilitates evaporation. [ABSTRACT FROM AUTHOR]

The binary heterostructured semiconducting visible light photocatalyst of the iron-doped graphitic carbon nitride/bismuth molybdate (Fe-g-C3N4/Bi2MoO6) composite was prepared by coupling with Fe-doped g-C3N4 and Bi2MoO6 particles. In the present study, a comparison of structural characteristics, optical properties, and photocatalytic degradation efficiency and activity between Fe-doped g-C3N4 particles, Bi2MoO6 particles, and Fe-g-C3N4/Bi2MoO6 composite was investigated. The results of X-ray diffraction (XRD) examination indicate that the hydrothermal Bi2MoO6 particles have a single orthorhombic phase and Fourier transform infrared (FTIR) spectroscopy analysis confirms the formation of Fe-doped g-C3N4. The optical bandgaps of the Fe-doped g-C3N4 and Bi2MoO6 particles are 2.74 and 2.73 eV, respectively, as estimated from the Taut plots obtained from UV-Vis diffuse reflectance spectroscopy (DRS) spectra. This characteristic indicates that the two semiconductor materials are suitable for absorbing visible light. The transmission electron microscopy (TEM) micrograph reveals the formation of the heterojunction Fe-g-C3N4/Bi2MoO6 composite. The results of photocatalytic degradation revealed that the developed Fe-g-C3N4/Bi2MoO6 composite photocatalyst exhibited significantly better photodegradation performance than the other two single semiconductor photocatalysts. This property can be attributed to the heterostructured nanostructure, which could effectively prevent the recombination of photogenerated carriers (electron–hole pairs) and enhance photocatalytic activity. Furthermore, cycling test showed that the Fe-g-C3N4/Bi2MoO6 heterostructured photocatalyst exhibited good reproducibility and stability for organic dye photodegradation. [ABSTRACT FROM AUTHOR]

Chamazulene (CA) is an intensely blue molecule with a wealth of biological properties. In cosmetics, chamazulene is exploited as a natural coloring and soothing agent. CA is unstable and tends to spontaneously degrade, accelerated by light. We studied the photodegradation of CA upon controlled exposure to UVB-UVA irradiation by multiple techniques, including GC-MS, UHPLC-PDA-ESI-MS/MS and by direct infusion in ESI-MSn, which were matched to in silico mass spectral simulations to identify degradation products. Seven byproducts formed upon UVA exposure for 3 h at 70 mW/cm2 (blue-to-green color change) were identified, including CA dimers and CA benzenoid, which were not found on extended 6 h irradiation (green-to-yellow fading). Photostability tests with reduced irradiance conducted in various solvents in the presence/absence of air indicated highest degradation in acetonitrile in the presence of oxygen, suggesting a photo-oxidative mechanism. Testing in the presence of antioxidants (tocopherol, ascorbyl palmitate, hydroxytyrosol, bakuchiol, γ-terpinene, TEMPO and their combinations) indicated the highest protection by tocopherol and TEMPO. Sunscreens ethylhexyl methoxycinnamate and particularly Tinosorb® S (but not octocrylene) showed good CA photoprotection. Thermal stability tests indicated no degradation of CA in acetonitrile at 50 °C in the dark for 50 days; however, accelerated degradation occurred in the presence of ascorbyl palmitate. [ABSTRACT FROM AUTHOR]

Advanced oxidation processes, including photocatalysis, have been proven effective at organic dye degradation. Tailored porous materials with regulated pore size, shape, and morphology offer a sustainable solution to the water pollution problem by acting as support materials to grafted photocatalytic nanoparticles (NPs). This research investigated the influence of pore and particle sizes of photocatalytic MICROSCAFS® on the degradation of methyl orange (MO) in aqueous solution (10 mg/L). Photocatalytic MICROSCAFS® are made of binder-less supported P25 TiO2 NPs within MICROSCAFS®, which are silica–titania microspheres with a controlled size and interconnected macroporosity, synthesized by an adapted sol–gel method that involves a polymerization-induced phase separation process. Photocatalytic experiments were performed both in batch and flow reactors, with this latter one targeting a proof of concept for continuous transformation processes and real-life conditions. Photocatalytic degradation of 87% in 2 h (batch) was achieved, using a calibrated solar light simulator (1 sun) and a photocatalyst/pollutant mass ratio of 23. This study introduces a novel flow kinetic model which provides the modeling and simulation of the photocatalytic MICROSCAFS® performance. A scavenger study was performed, enabling an in-depth mechanistic understanding. Finally, the transformation products resulting from the MO photocatalytic degradation were elucidated by high-resolution mass spectrometry experiments and subjected to an in silico toxicity assessment. [ABSTRACT FROM AUTHOR]

In this study, nanoporous TiO2 with hierarchical micro/nanostructures was synthesized on a large scale by a facile one-step solvothermal method at a low temperature. A series of characterizations was performed and carried out on the as-prepared photocatalysts, which were applied to the degradation of the antibiotic tetracycline (TC). The results demonstrated that nanoporous TiO2 obtained at a solvothermal temperature of 100 °C had a spherical morphology with high crystallinity and a relatively large specific surface area, composed of a large number of nanospheres. The nanoporous TiO2 with hierarchical micro/nanostructures exhibited excellent photocatalytic degradation activity for TC under simulated sunlight. The degradation rate was close to 100% after 30 min of UV light irradiation, and reached 79% only after 60 min of visible light irradiation, which was much better than the photodegradation performance of commercial TiO2 (only 29%). Moreover, the possible intermediates formed during the photocatalytic degradation of TC were explored by the density functional theory calculations and HPLC-MS spectra. Furthermore, two possible degradation routes were proposed, which provided experimental and theoretical support for the photocatalytic degradation of TC. In this study, we provide a new approach for the hierarchical micro/nanostructure of nanoporous TiO2, which can be applied in industrial manufacturing fields. [ABSTRACT FROM AUTHOR]

Magnetic separation of photocatalysts holds great promise for water treatment. A magnetic separation method has a positive effect on the recovery of catalysts after degradation. In this paper, an efficient and reusable catalytic system is developed based on coating magnetic Fe3O4 by depositing Fe2+ on the surface of ZnO. The Fe3O4/ZnO nanocomposite exhibits enhanced performance for organic pollutant degradation. The Fe3O4/ZnO system demonstrates a high photocatalytic activity of 100% degradation efficiency in Rhodamine B (RhB) degradation under UV light irradiation for 50 min. The excellent photocatalytic activity is primarily due to the separation of photogenerated electron-hole pairs being facilitated by the strong interaction between Fe3O4 and ZnO. The induction of the magnetic Fe3O4 endows the Fe3O4/ZnO composite with superior magnetic separation capability from water. Experiments with different radical scavengers revealed that the hydroxyl radical (·OH) is the key reactive radical for the effective degradation of RhB. This work innovatively affords a common interfacial dopant deposition strategy for catalytic application in the degradation of organic dye pollutants and catalyst separation from wastewater efficiently. [ABSTRACT FROM AUTHOR]

Creating oxygen vacancy in tungsten trioxide (WO3) has been considered as an effective strategy to improve the photocatalytic performance for degrading organic pollutants. In this study, oxygen vacancies were introduced into WO3 by thermal treatment under Ar atmosphere and their proportion was changed by setting different treatment times. WO3−x samples show better photoelectric properties and photocatalytic degradation performance for carbamazepine (CBZ) than an oxygen-vacancy-free sample, and WO3−x with the optimal proportion of oxygen vacancies is obtained by thermal treatment for 3 h in 550 °C. Furthermore, it discovers that the surface oxygen vacancies on WO3−x would be recovered when it is exposed to air, resulting in a bulk oxygen vacancy dominating WO3−x (bulk-WO3−x). The bulk-WO3−x exhibited much higher degradation efficiency for CBZ than WO3−x with both surface and bulk oxygen vacancies. The mechanism study shows bulk-WO3−x mainly degrades the CBZ by producing OH radicals and superoxide radicals, while oxygen-vacancy-free sample mainly oxidizes the CBZ by the photoexcited hole, which requires the CBZ to be adsorbed on the surface for degradation. The radical generated by bulk-WO3−x exhibits stronger oxidizing capacity by migrating to the solution for CBZ degradation. In summary, the influence of oxygen vacancy on photocatalytic degradation performance depends on both the proportion and location distribution and could lie in the optimization of the photodegradation mechanism. The results of this study could potentially broaden our understanding of the role of oxygen vacancies and provide optimal directions and methods for oxygen vacancy regulation for photocatalysts. [ABSTRACT FROM AUTHOR]

Microplastics (MPs) pose a profound environmental challenge, impacting ecosystems and human health through mechanisms such as bioaccumulation and ecosystem contamination. While traditional water treatment methods can partially remove microplastics, their limitations highlight the need for innovative green approaches like photodegradation to ensure more effective and sustainable removal. This review explores the potential of nanomaterial-enhanced photocatalysts in addressing this issue. Utilizing their unique properties like large surface area and tunable bandgap, nanomaterials significantly improve degradation efficiency. Different strategies for photocatalyst modification to improve photocatalytic performance are thoroughly summarized, with a particular emphasis on element doping and heterojunction construction. Furthermore, this review thoroughly summarizes the possible fundamental mechanisms driving the photodegradation of microplastics facilitated by nanomaterials, with a focus on processes like free radical formation and singlet oxygen oxidation. This review not only synthesizes critical findings from existing studies but also identifies gaps in the current research landscape, suggesting that further development of these photocatalytic techniques could lead to substantial advancements in environmental remediation practices. By delineating these novel approaches and their mechanisms, this work underscores the significant environmental implications and contributes to the ongoing development of sustainable solutions to mitigate microplastic pollution. [ABSTRACT FROM AUTHOR]

This work aims to evaluate the potential use of natural wastes (in particular, clam shells) to synthesize one of the most well-known and versatile materials from the phosphate mineral group, hydroxyapatite (HAP). The obtained material was characterized in terms of morphology and composition using several analytical methods (scanning electron microscopy—SEM, X-ray diffraction—XRD, X-ray fluorescence—XRF, Fourier transform infrared spectroscopy—FTIR, thermal analysis—TGA, and evaluation of the porosity and specific surface characteristics by the Brunauer–Emmett–Teller—BET method) in order to confirm the successful synthesis of the material and to evaluate the presence of potential secondary phases. The developed material was further doped with iron oxide (HAP-Fe) using a microwave-assisted method, and both materials were evaluated in terms of photocatalytic activity determined by the photodecomposition of methylene blue (MB) which served as a contaminant model. The best results (approx. 33% MB degradation efficiency, after 120 min. of exposure) were obtained for the hydroxyapatite material, superior to the HAP-Fe composite (approx. 27%). The utilization of hydroxyapatite obtained from clam shells underscores the importance of sustainable and eco-friendly practices in materials syntheses. By repurposing waste materials from the seafood industry, we not only reduce environmental impact, but also create a valuable resource with diverse applications, contributing to advancements in both healthcare and environmental protection. [ABSTRACT FROM AUTHOR]

Antibiotic residues have been found to have potentially harmful effects on ecological and human health. Carbon nitride-based photocatalysts have widely focused on antibiotic photocatalytic degradation. Herein, we prepared Fe-modified g-C3N4 nanorod bunches (FCNBs) using chemical vapor co-deposition. Specifically, through the process of calcination, a blend of urea and chlorophyllin sodium iron salt underwent an intriguing transformation, resulting in the integration of Fe into the framework of the g-C3N4 nanorod cluster. The resulting photocatalyst exhibited remarkable stability and superior dispersibility. The prepared FCNBs had a unique structure, which was beneficial for increasing light absorption. Furthermore, the Fe species formed a chemical coordination with the g-C3N4 matrix, thereby altering the electronic structure of the matrix. This modification facilitated charge transfer, prolonged the carrier lifetime, and enhanced light absorption, all of which significantly increased the photocatalytic activity. The oxytetracycline degradation efficiency of FCNBs was 82.5%, and they demonstrated outstanding stability in cycle trials. This work introduces a promising photocatalyst for the degradation of antibiotics. [ABSTRACT FROM AUTHOR]

In this study, the photocatalytic degradation of phenol, which is commonly found in industrial wastewater at high rates, was investigated using a zinc oxide (ZnO) catalyst. It is thought that our findings will contribute to the removal of phenol in industrial wastewater. The experimental study was conducted in a batch‐type air‐fed cylindrical photocatalytic reactor, and a central composite design (CCD) was chosen and analyzed using response surface methodology (RSM). The study aimed to explore the effects of initial phenol concentration, catalyst concentration, airflow rate, and degradation time on the photocatalytic degradation of phenol and the removal efficiency of total organic carbon (TOC). A quadratic regression model was developed to establish the relationship between phenol degradation, TOC removal effectiveness, and the four factors mentioned. The validity of the model was assessed through an analysis of variance (ANOVA). A good agreement was observed between the model results and the experimental data. As a result of the experiments carried out under optimized conditions, the degradation percentage of phenol was found to be 77.15 %, and the degradation percentage of TOC was 59.87 %. Additionally, pseudo‐first‐order kinetics were used in the photocatalytic degradation of phenol. [ABSTRACT FROM AUTHOR]

In this paper, a titanium dioxide/covalent organic framework (TiO2/COF) composite was prepared and its photocatalytic removal of dye was investigated. Using tetrabutyl titanate as a titanium source, TiO2 nanomaterial was prepared by sol‐gel method. In the presence of TiO2, TiO2/COF core‐shell composite was prepared by solvothermal synthesis using melamine and 1,4‐phthalaldehyde as ligands. The prepared materials are characterized by SEM, TEM, XPS, XRD, TG, FTIR, BET, EPR, PL, and UV‐Vis‐DRS techniques. Using malachite green as a model of dye wastewater, the photocatalytic degradation performance of TiO2/COF composites was investigated under the irradiation of ultraviolet light. The results show that the modification of COF significantly improves the photocatalytic efficiency of TiO2, the degradation rate increases from 69.77 % to 93.64 %, and the reaction rate constant of the first‐order kinetic equation is increased from 0.0078 min−1 to 0.0192 min−1. Based on the free radical capture experiment, the photocatalytic degradation mechanism of TiO2/COF was discussed, and the feasibility of its photocatalytic degradation of malachite green was theoretically clarified. Accordingly, a simple and practical method for photocatalytic degradation of malachite green was constructed, which has potential application value in the degradation of dye wastewater. [ABSTRACT FROM AUTHOR]

The photocatalysis process, which is effective, economical, and environmentally friendly can overcome rapidly increasing environmental problems, has shown rapid development in recent years. Nontoxic, low-cost natural minerals are often used in photocatalysis processes that remove organic pollution from wastewater. In this study, a selective method for the removal of crystal violet (CV) from aqueous solutions using nanocomposite of nickel oxide/zinc oxide nanoparticles (NiO/ZnO) supported on kaolinite photocatalyst was investigated. The raw kaolinite, bare NiO, bare ZnO and nanocomposite samples were characterized by the XRD, TEM, SEM-EDX, XPS and FTIR techniques. The photocatalytic performances of kaolinite-NiOZnO (K-NiO/ZnO) nanocomposite and bare samples were also investigated and comparatively evaluated by the photodegradation of CV (cationic dye) dye under visible light irradiation. The effects of various parameters such as the dosage of photocatalysis, contact time, and initial dye concentration on the rate of removal of dye were investigated and optimized. The kinetics of decolorization by samples can be well described by the pseudo-first-order model. Finally, it can be used in advanced oxidative processes for the degradation of organic pollutants. [ABSTRACT FROM AUTHOR]